ABSTRACT
The growth of the modern city is characterized by the operation of centripetal forces, which were predominant during the 19th century, and by centrifugal forces that have become more important during the present century. The expansion of the urban area has been marked, especially since about 1880, by specialization of function and by the segregation of related structures in districts or zones. This expansion, whether by accretion or centrifugal spread, and the functional differentiation of districts, centred on the business and cultural core, is the essence of the process of modern urban growth. This has already been examined in general terms in a previous book, City, Region and Regionalism, and the main facts are summarized as follows in the light of the detailed specific studies of various aspects of this growth in different cities that have been presented in Part I.
